import javax.print.attribute.HashPrintRequestAttributeSet;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User:何人亮
 * Date:2024-05-30
 * 20:02
 */
public class toLower {
    public static String tolower(String s){
       StringBuilder stringBuilder=new StringBuilder();
        for (int i = 0; i < s.length(); i++) {
            char ch=s.charAt(i);
            if (Character.isLetter(ch)){
                if(Character.isUpperCase(ch)){
                    ch=(char)(ch+32);
                }

            }
            stringBuilder.append(ch);
        }
        return stringBuilder.toString();
    }
    public static void main(String[] args) {
        String ss=tolower("skKFK344e#&JFkkd");
        System.out.println(ss);

    }
}
